by: Heather Smith Thomas
The first use of artificial insemination was accomplished by Arab Sheiks who wanted to utilize bloodlines of tribal enemies. They would sneak up to the other tribe's herd at night with a mare in heat secretly collect semen from the stallion into a leather pouch and take it back to their own camp to inseminate a prize mare.
Artificial insemination in the United States was first used in dairy herds in the 1930s with cooled fresh liquid semen – transported in glass vials kept cool in ice water. Most AI studs were local, because fresh semen couldn't be transported very far.
The advent of frozen semen revolutionized this process. Beef AI got started in the early 1950s along with performance testing of certain bulls. Some progeny testing was done in the late 1960s and early 1970s by the Beef Improvement Federation. Importations of some European breeds were only possible by using frozen semen and AI, due to restrictions on importing live animals.
Today, the AI process is easier with use of synchronization protocols. All the cows in the herd can be bred on the same day instead of having to watch them for signs of heat. Conception rates have also improved.
Being able to ultrasound the cow's ovaries and determine the time of ovulation helped researchers figure out the best time to inseminate cattle and obtain better conception rates.
Willie Altenburg, a cattleman in northern Colorado who also works for Genex (a company that supplies a lot of semen for AI) said heat synchronization and artificial insemination have worked very well for heifers for many years. "Heat synchronization has become commonplace for heifers. It has become a management tool for many producers," he said.
''We were struggling more with cow AI, however. The advent of the CIDR [controlled internal drug release] and use of prostaglandin has really helped us in that area, so we've been doing more cow AI. Synchronization and fixed time insemination has helped a lot when working with cows, but we need an army of arms to get this accomplished. Most producers can't breed 100 cows in one morning, and it can also be a challenge with their facilities.
"The AI organizations now have portable breeding barns and technicians who can come to your place to do this service -- and get those cows all bred in a few hours," said Altenburg.
Progress in AI techniques has been aided by the Beef Reproductive Task Force and Reproductive Leadership Team, figuring out the best AI protocols. The Task Force is a group of researchers who work with beef reproduction at various universities, doing research on estrous synchronization and AI. The Leadership Team includes representatives from the Task Force, AI studs, the pharmaceutical industry, and veterinarians.
This group came up with recommended estrous synchronization protocols for AI after looking at research from all the universities on different AI systems. Whenever something new looks promising, the data is analyzed to see if there are enough numbers for valid conclusions, and whether it is consistent enough to say it's better than what was being done before.
"We hold conferences on applied reproductive strategies, and the committee that is formed each year updates those protocols. We try to make those almost foolproof. We tell producers to stay with those and not deviate from them. I tell my clients to let the researchers do the research, and apply what the research has proven to work," he said.
"Now the CIDRs have allowed us to be more successful with cow AI and the systems have improved so much that we are doing this a lot more. Only about 15 to 18 percent of cow herds are heifers, so that's a small part of the female population that we can AI. We can make so much more improvement if we can move to the cowherd.
"Our goal is to have six out of every 10 animals that leave the breeding shed be pregnant on the first day of the breeding season. Those numbers get breeders' attention. When you say 60 percent pregnancy rate that doesn't sound very good, but when you say this another way -- that six out of every 10 females are pregnant on the first day of breeding season -- this makes a difference, especially in terms of your needed bull power, with bulls at $5,000 to $10,000 a piece."
At an AI school at Fort Collins a few years ago, the cost of using AI versus buying bulls was discussed.
"I asked the producers to give me their numbers. They argued about what it would cost to buy a bull. Some said $3,000 and some said $5,000. There was a lot of discussion and they finally came to a $4,500 figure -- even though some producers said it needs to be higher and others said they couldn't afford bulls that high," said Altenburg. The price for bulls has gone up even more since then.
The cost per pregnancy for a bull, figuring in the fences that he wrecked and the feed he ate, if you used him for 3.5 years and he gave you 25 calves per year, was estimated at $74 per calf. "Then we figured the AI side, with fixed time insemination, breeding the cows, and cleanup bulls, and came up with $62 per calf. The producers were a bit surprised, but realized that AI has never been more affordable, with the high cost of bulls," he said. Today, AI is even more attractive because the bulls are even more expensive.
"We are also utilizing DNA markers in our selections for the bulls that come into AI programs, and some producers are even using DNA when making selection on their yearling bulls to improve the accuracy. This is exciting," Altenburg said.
With the cost of AI and the cost of bulls, more large herds are incorporating AI into their business plan. "It is very affordable, and the expertise of the people who come into these ranches (to give a full-service program to quickly get the job done) can easily get 60 percent of the females pregnant on the first day of AI season," he noted. Having that many females pregnant early in the season is always a plus and makes the producer money.
Some of the newer reproductive technologies available today include embryo transfer and sexed semen, but the average commercial cowman isn't going to use these tools.
"Of all the things that I've tried in my own operation, including embryo transfer and sorted semen, AI has made me a lot more money than anything else I've ever done. The more AI calves I can get, the more improvement I can get," Altenburg said.
You can select the genetics you want for certain traits. You can breed heifers to calving-ease bulls with high growth and good maternal traits (and keep replacement heifers from that group) and breed the cows to a high performance bull or terminal sire for bigger calves to sell or to make you money on retained ownership through the feeding phase.
"I make more money with an $18 straw of semen than I do with anything else I do with my cows," he said.
Some of the newer technologies may also become more affordable in the future. The sorted semen from Genex (GenChoice, from Sexing Technologies, the company that holds the patent to the sorting process) at this point has a lower conception rate than regular AI, however.
"We get about 8 to 10 percent reduction in conception using sexed semen, but the flip side is that we get very good results on the sex," he explains.
"Sexed semen allows you to do several things. If you are breeding heifers you can use heifer semen to reduce dystocia (since heifer calves tend to be smaller at birth than bull calves), and then you can keep replacements out of your heifers because hopefully they will be your best genetics. If you are in the bull business, you can produce males and sell $5,000 to $10,000 bulls instead of $2,000 heifers. There are so many positive ways that it can work for various breeders."
Editor's Note: For information on the Beef Reproduction Task Force and Applied Reproductive Strategies in Beef Cattle, go online to appliedreproductivestrategies. com.
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